The present invention relates to a wireless microphone; specifically, the present invention relates to a wireless microphone comprising a radio transmitter for transmitting radio signals carrying audio signals to a hearing device.
Wireless microphones are used as assistive listening devices for transmitting sound from the sound source directly to a hearing device arranged in or at a person's ear, whereby the signal-to-noise ratio is greatly improved. The wireless microphones currently available for that purpose comprise radio transmitters for transmitting radio signals that carry audio signals to a radio receiver of a hearing aid, for example a behind-the-ear (BTE) hearing instrument, or to a radio receiver with an electro-acoustic converter reproducing the sound directly into the ear. Common applications of wireless microphones as assistive listening devices include applications in schools, where the teacher wears the wireless microphone and the hearing impaired student wears a receiver connected to his hearing aid. The wireless microphone is also used in business meetings or in restaurants, where the wireless microphone is placed on a table. The wireless microphones are also useful for listening to the sound of a television or a stereo set without turning up the volume. Typically, the known wireless microphones suitable as assistive listening devices are equipped to receive electrical audio signals through wire connections from external audio sources such as a television or a stereo set. However, the users often find the connective wires not very practical. Because the wireless microphone needs to be placed at wire's length from the audio source, the wireless microphone is not always within reach of the user. The known wireless microphones often comprise omnidirectional and/or beam-forming microphones. Moreover, for recharging the power source, the known wireless microphones comprise charging circuits. Although these additional features are not used all the time, they consume power and the components used for their implementation increase the weight of the wireless microphone. Other features or functions which could be of interest to the users are currently not available and cannot be added to the known wireless microphones.